xref: /linux/drivers/hwmon/lm87.c (revision 02892f90a9851f508e557b3c75e93fc178310d5f)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * lm87.c
4  *
5  * Copyright (C) 2000       Frodo Looijaard <frodol@dds.nl>
6  *                          Philip Edelbrock <phil@netroedge.com>
7  *                          Stephen Rousset <stephen.rousset@rocketlogix.com>
8  *                          Dan Eaton <dan.eaton@rocketlogix.com>
9  * Copyright (C) 2004-2008  Jean Delvare <jdelvare@suse.de>
10  *
11  * Original port to Linux 2.6 by Jeff Oliver.
12  *
13  * The LM87 is a sensor chip made by National Semiconductor. It monitors up
14  * to 8 voltages (including its own power source), up to three temperatures
15  * (its own plus up to two external ones) and up to two fans. The default
16  * configuration is 6 voltages, two temperatures and two fans (see below).
17  * Voltages are scaled internally with ratios such that the nominal value of
18  * each voltage correspond to a register value of 192 (which means a
19  * resolution of about 0.5% of the nominal value). Temperature values are
20  * reported with a 1 deg resolution and a 3-4 deg accuracy. Complete
21  * datasheet can be obtained from National's website at:
22  *   http://www.national.com/pf/LM/LM87.html
23  *
24  * Some functions share pins, so not all functions are available at the same
25  * time. Which are depends on the hardware setup. This driver normally
26  * assumes that firmware configured the chip correctly. Where this is not
27  * the case, platform code must set the I2C client's platform_data to point
28  * to a u8 value to be written to the channel register.
29  * For reference, here is the list of exclusive functions:
30  *  - in0+in5 (default) or temp3
31  *  - fan1 (default) or in6
32  *  - fan2 (default) or in7
33  *  - VID lines (default) or IRQ lines (not handled by this driver)
34  *
35  * The LM87 additionally features an analog output, supposedly usable to
36  * control the speed of a fan. All new chips use pulse width modulation
37  * instead. The LM87 is the only hardware monitoring chipset I know of
38  * which uses amplitude modulation. Be careful when using this feature.
39  *
40  * This driver also supports the ADM1024, a sensor chip made by Analog
41  * Devices. That chip is fully compatible with the LM87. Complete
42  * datasheet can be obtained from Analog's website at:
43  *   https://www.analog.com/en/prod/0,2877,ADM1024,00.html
44  */
45 
46 #include <linux/module.h>
47 #include <linux/init.h>
48 #include <linux/slab.h>
49 #include <linux/jiffies.h>
50 #include <linux/i2c.h>
51 #include <linux/hwmon.h>
52 #include <linux/hwmon-sysfs.h>
53 #include <linux/hwmon-vid.h>
54 #include <linux/err.h>
55 #include <linux/mutex.h>
56 #include <linux/regulator/consumer.h>
57 
58 /*
59  * Addresses to scan
60  * LM87 has three possible addresses: 0x2c, 0x2d and 0x2e.
61  */
62 
63 static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
64 
65 /*
66  * The LM87 registers
67  */
68 
69 /* nr in 0..5 */
70 #define LM87_REG_IN(nr)			(0x20 + (nr))
71 #define LM87_REG_IN_MAX(nr)		(0x2B + (nr) * 2)
72 #define LM87_REG_IN_MIN(nr)		(0x2C + (nr) * 2)
73 /* nr in 0..1 */
74 #define LM87_REG_AIN(nr)		(0x28 + (nr))
75 #define LM87_REG_AIN_MIN(nr)		(0x1A + (nr))
76 #define LM87_REG_AIN_MAX(nr)		(0x3B + (nr))
77 
78 static u8 LM87_REG_TEMP[3] = { 0x27, 0x26, 0x20 };
79 static u8 LM87_REG_TEMP_HIGH[3] = { 0x39, 0x37, 0x2B };
80 static u8 LM87_REG_TEMP_LOW[3] = { 0x3A, 0x38, 0x2C };
81 
82 #define LM87_REG_TEMP_HW_INT_LOCK	0x13
83 #define LM87_REG_TEMP_HW_EXT_LOCK	0x14
84 #define LM87_REG_TEMP_HW_INT		0x17
85 #define LM87_REG_TEMP_HW_EXT		0x18
86 
87 /* nr in 0..1 */
88 #define LM87_REG_FAN(nr)		(0x28 + (nr))
89 #define LM87_REG_FAN_MIN(nr)		(0x3B + (nr))
90 #define LM87_REG_AOUT			0x19
91 
92 #define LM87_REG_CONFIG			0x40
93 #define LM87_REG_CHANNEL_MODE		0x16
94 #define LM87_REG_VID_FAN_DIV		0x47
95 #define LM87_REG_VID4			0x49
96 
97 #define LM87_REG_ALARMS1		0x41
98 #define LM87_REG_ALARMS2		0x42
99 
100 #define LM87_REG_COMPANY_ID		0x3E
101 #define LM87_REG_REVISION		0x3F
102 
103 /*
104  * Conversions and various macros
105  * The LM87 uses signed 8-bit values for temperatures.
106  */
107 
108 #define IN_FROM_REG(reg, scale)	(((reg) * (scale) + 96) / 192)
109 #define IN_TO_REG(val, scale)	((val) <= 0 ? 0 : \
110 				 (val) >= (scale) * 255 / 192 ? 255 : \
111 				 ((val) * 192 + (scale) / 2) / (scale))
112 
113 #define TEMP_FROM_REG(reg)	((reg) * 1000)
114 #define TEMP_TO_REG(val)	((val) <= -127500 ? -128 : \
115 				 (val) >= 126500 ? 127 : \
116 				 (((val) < 0 ? (val) - 500 : \
117 				   (val) + 500) / 1000))
118 
119 static int fan_from_reg(int reg, int div)
120 {
121 	if (reg == 255 || reg == 0)
122 		return 0;
123 
124 	return (1350000 + reg * div / 2) / (reg * div);
125 }
126 
127 #define FAN_TO_REG(val, div)	((val) * (div) * 255 <= 1350000 ? 255 : \
128 				 (1350000 + (val)*(div) / 2) / ((val) * (div)))
129 
130 #define FAN_DIV_FROM_REG(reg)	(1 << (reg))
131 
132 /* analog out is 9.80mV/LSB */
133 #define AOUT_FROM_REG(reg)	(((reg) * 98 + 5) / 10)
134 #define AOUT_TO_REG(val)	((val) <= 0 ? 0 : \
135 				 (val) >= 2500 ? 255 : \
136 				 ((val) * 10 + 49) / 98)
137 
138 /* nr in 0..1 */
139 #define CHAN_NO_FAN(nr)		(1 << (nr))
140 #define CHAN_TEMP3		(1 << 2)
141 #define CHAN_VCC_5V		(1 << 3)
142 #define CHAN_NO_VID		(1 << 7)
143 
144 /*
145  * Client data (each client gets its own)
146  */
147 
148 struct lm87_data {
149 	struct mutex update_lock;
150 	bool valid; /* false until following fields are valid */
151 	unsigned long last_updated; /* In jiffies */
152 
153 	u8 channel;		/* register value */
154 	u8 config;		/* original register value */
155 
156 	u8 in[8];		/* register value */
157 	u8 in_max[8];		/* register value */
158 	u8 in_min[8];		/* register value */
159 	u16 in_scale[8];
160 
161 	s8 temp[3];		/* register value */
162 	s8 temp_high[3];	/* register value */
163 	s8 temp_low[3];		/* register value */
164 	s8 temp_crit_int;	/* min of two register values */
165 	s8 temp_crit_ext;	/* min of two register values */
166 
167 	u8 fan[2];		/* register value */
168 	u8 fan_min[2];		/* register value */
169 	u8 fan_div[2];		/* register value, shifted right */
170 	u8 aout;		/* register value */
171 
172 	u16 alarms;		/* register values, combined */
173 	u8 vid;			/* register values, combined */
174 	u8 vrm;
175 
176 	const struct attribute_group *attr_groups[6];
177 };
178 
179 static inline int lm87_read_value(struct i2c_client *client, u8 reg)
180 {
181 	return i2c_smbus_read_byte_data(client, reg);
182 }
183 
184 static inline int lm87_write_value(struct i2c_client *client, u8 reg, u8 value)
185 {
186 	return i2c_smbus_write_byte_data(client, reg, value);
187 }
188 
189 static struct lm87_data *lm87_update_device(struct device *dev)
190 {
191 	struct i2c_client *client = dev_get_drvdata(dev);
192 	struct lm87_data *data = i2c_get_clientdata(client);
193 
194 	mutex_lock(&data->update_lock);
195 
196 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
197 		int i, j;
198 
199 		dev_dbg(&client->dev, "Updating data.\n");
200 
201 		i = (data->channel & CHAN_TEMP3) ? 1 : 0;
202 		j = (data->channel & CHAN_TEMP3) ? 5 : 6;
203 		for (; i < j; i++) {
204 			data->in[i] = lm87_read_value(client,
205 				      LM87_REG_IN(i));
206 			data->in_min[i] = lm87_read_value(client,
207 					  LM87_REG_IN_MIN(i));
208 			data->in_max[i] = lm87_read_value(client,
209 					  LM87_REG_IN_MAX(i));
210 		}
211 
212 		for (i = 0; i < 2; i++) {
213 			if (data->channel & CHAN_NO_FAN(i)) {
214 				data->in[6+i] = lm87_read_value(client,
215 						LM87_REG_AIN(i));
216 				data->in_max[6+i] = lm87_read_value(client,
217 						    LM87_REG_AIN_MAX(i));
218 				data->in_min[6+i] = lm87_read_value(client,
219 						    LM87_REG_AIN_MIN(i));
220 
221 			} else {
222 				data->fan[i] = lm87_read_value(client,
223 					       LM87_REG_FAN(i));
224 				data->fan_min[i] = lm87_read_value(client,
225 						   LM87_REG_FAN_MIN(i));
226 			}
227 		}
228 
229 		j = (data->channel & CHAN_TEMP3) ? 3 : 2;
230 		for (i = 0 ; i < j; i++) {
231 			data->temp[i] = lm87_read_value(client,
232 					LM87_REG_TEMP[i]);
233 			data->temp_high[i] = lm87_read_value(client,
234 					     LM87_REG_TEMP_HIGH[i]);
235 			data->temp_low[i] = lm87_read_value(client,
236 					    LM87_REG_TEMP_LOW[i]);
237 		}
238 
239 		i = lm87_read_value(client, LM87_REG_TEMP_HW_INT_LOCK);
240 		j = lm87_read_value(client, LM87_REG_TEMP_HW_INT);
241 		data->temp_crit_int = min(i, j);
242 
243 		i = lm87_read_value(client, LM87_REG_TEMP_HW_EXT_LOCK);
244 		j = lm87_read_value(client, LM87_REG_TEMP_HW_EXT);
245 		data->temp_crit_ext = min(i, j);
246 
247 		i = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
248 		data->fan_div[0] = (i >> 4) & 0x03;
249 		data->fan_div[1] = (i >> 6) & 0x03;
250 		data->vid = (i & 0x0F)
251 			  | (lm87_read_value(client, LM87_REG_VID4) & 0x01)
252 			     << 4;
253 
254 		data->alarms = lm87_read_value(client, LM87_REG_ALARMS1)
255 			     | (lm87_read_value(client, LM87_REG_ALARMS2)
256 				<< 8);
257 		data->aout = lm87_read_value(client, LM87_REG_AOUT);
258 
259 		data->last_updated = jiffies;
260 		data->valid = true;
261 	}
262 
263 	mutex_unlock(&data->update_lock);
264 
265 	return data;
266 }
267 
268 /*
269  * Sysfs stuff
270  */
271 
272 static ssize_t in_input_show(struct device *dev,
273 			     struct device_attribute *attr, char *buf)
274 {
275 	struct lm87_data *data = lm87_update_device(dev);
276 	int nr = to_sensor_dev_attr(attr)->index;
277 
278 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in[nr],
279 		       data->in_scale[nr]));
280 }
281 
282 static ssize_t in_min_show(struct device *dev, struct device_attribute *attr,
283 			   char *buf)
284 {
285 	struct lm87_data *data = lm87_update_device(dev);
286 	int nr = to_sensor_dev_attr(attr)->index;
287 
288 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_min[nr],
289 		       data->in_scale[nr]));
290 }
291 
292 static ssize_t in_max_show(struct device *dev, struct device_attribute *attr,
293 			   char *buf)
294 {
295 	struct lm87_data *data = lm87_update_device(dev);
296 	int nr = to_sensor_dev_attr(attr)->index;
297 
298 	return sprintf(buf, "%u\n", IN_FROM_REG(data->in_max[nr],
299 		       data->in_scale[nr]));
300 }
301 
302 static ssize_t in_min_store(struct device *dev, struct device_attribute *attr,
303 			    const char *buf, size_t count)
304 {
305 	struct i2c_client *client = dev_get_drvdata(dev);
306 	struct lm87_data *data = i2c_get_clientdata(client);
307 	int nr = to_sensor_dev_attr(attr)->index;
308 	long val;
309 	int err;
310 
311 	err = kstrtol(buf, 10, &val);
312 	if (err)
313 		return err;
314 
315 	mutex_lock(&data->update_lock);
316 	data->in_min[nr] = IN_TO_REG(val, data->in_scale[nr]);
317 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MIN(nr) :
318 			 LM87_REG_AIN_MIN(nr - 6), data->in_min[nr]);
319 	mutex_unlock(&data->update_lock);
320 	return count;
321 }
322 
323 static ssize_t in_max_store(struct device *dev, struct device_attribute *attr,
324 			    const char *buf, size_t count)
325 {
326 	struct i2c_client *client = dev_get_drvdata(dev);
327 	struct lm87_data *data = i2c_get_clientdata(client);
328 	int nr = to_sensor_dev_attr(attr)->index;
329 	long val;
330 	int err;
331 
332 	err = kstrtol(buf, 10, &val);
333 	if (err)
334 		return err;
335 
336 	mutex_lock(&data->update_lock);
337 	data->in_max[nr] = IN_TO_REG(val, data->in_scale[nr]);
338 	lm87_write_value(client, nr < 6 ? LM87_REG_IN_MAX(nr) :
339 			 LM87_REG_AIN_MAX(nr - 6), data->in_max[nr]);
340 	mutex_unlock(&data->update_lock);
341 	return count;
342 }
343 
344 static SENSOR_DEVICE_ATTR_RO(in0_input, in_input, 0);
345 static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
346 static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
347 static SENSOR_DEVICE_ATTR_RO(in1_input, in_input, 1);
348 static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
349 static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
350 static SENSOR_DEVICE_ATTR_RO(in2_input, in_input, 2);
351 static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
352 static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
353 static SENSOR_DEVICE_ATTR_RO(in3_input, in_input, 3);
354 static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
355 static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
356 static SENSOR_DEVICE_ATTR_RO(in4_input, in_input, 4);
357 static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
358 static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
359 static SENSOR_DEVICE_ATTR_RO(in5_input, in_input, 5);
360 static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
361 static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
362 static SENSOR_DEVICE_ATTR_RO(in6_input, in_input, 6);
363 static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
364 static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
365 static SENSOR_DEVICE_ATTR_RO(in7_input, in_input, 7);
366 static SENSOR_DEVICE_ATTR_RW(in7_min, in_min, 7);
367 static SENSOR_DEVICE_ATTR_RW(in7_max, in_max, 7);
368 
369 static ssize_t temp_input_show(struct device *dev,
370 			       struct device_attribute *attr, char *buf)
371 {
372 	struct lm87_data *data = lm87_update_device(dev);
373 	int nr = to_sensor_dev_attr(attr)->index;
374 
375 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp[nr]));
376 }
377 
378 static ssize_t temp_low_show(struct device *dev,
379 			     struct device_attribute *attr, char *buf)
380 {
381 	struct lm87_data *data = lm87_update_device(dev);
382 	int nr = to_sensor_dev_attr(attr)->index;
383 
384 	return sprintf(buf, "%d\n",
385 		       TEMP_FROM_REG(data->temp_low[nr]));
386 }
387 
388 static ssize_t temp_high_show(struct device *dev,
389 			      struct device_attribute *attr, char *buf)
390 {
391 	struct lm87_data *data = lm87_update_device(dev);
392 	int nr = to_sensor_dev_attr(attr)->index;
393 
394 	return sprintf(buf, "%d\n",
395 		       TEMP_FROM_REG(data->temp_high[nr]));
396 }
397 
398 static ssize_t temp_low_store(struct device *dev,
399 			      struct device_attribute *attr, const char *buf,
400 			      size_t count)
401 {
402 	struct i2c_client *client = dev_get_drvdata(dev);
403 	struct lm87_data *data = i2c_get_clientdata(client);
404 	int nr = to_sensor_dev_attr(attr)->index;
405 	long val;
406 	int err;
407 
408 	err = kstrtol(buf, 10, &val);
409 	if (err)
410 		return err;
411 
412 	mutex_lock(&data->update_lock);
413 	data->temp_low[nr] = TEMP_TO_REG(val);
414 	lm87_write_value(client, LM87_REG_TEMP_LOW[nr], data->temp_low[nr]);
415 	mutex_unlock(&data->update_lock);
416 	return count;
417 }
418 
419 static ssize_t temp_high_store(struct device *dev,
420 			       struct device_attribute *attr, const char *buf,
421 			       size_t count)
422 {
423 	struct i2c_client *client = dev_get_drvdata(dev);
424 	struct lm87_data *data = i2c_get_clientdata(client);
425 	int nr = to_sensor_dev_attr(attr)->index;
426 	long val;
427 	int err;
428 
429 	err = kstrtol(buf, 10, &val);
430 	if (err)
431 		return err;
432 
433 	mutex_lock(&data->update_lock);
434 	data->temp_high[nr] = TEMP_TO_REG(val);
435 	lm87_write_value(client, LM87_REG_TEMP_HIGH[nr], data->temp_high[nr]);
436 	mutex_unlock(&data->update_lock);
437 	return count;
438 }
439 
440 static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
441 static SENSOR_DEVICE_ATTR_RW(temp1_min, temp_low, 0);
442 static SENSOR_DEVICE_ATTR_RW(temp1_max, temp_high, 0);
443 static SENSOR_DEVICE_ATTR_RO(temp2_input, temp_input, 1);
444 static SENSOR_DEVICE_ATTR_RW(temp2_min, temp_low, 1);
445 static SENSOR_DEVICE_ATTR_RW(temp2_max, temp_high, 1);
446 static SENSOR_DEVICE_ATTR_RO(temp3_input, temp_input, 2);
447 static SENSOR_DEVICE_ATTR_RW(temp3_min, temp_low, 2);
448 static SENSOR_DEVICE_ATTR_RW(temp3_max, temp_high, 2);
449 
450 static ssize_t temp1_crit_show(struct device *dev,
451 			       struct device_attribute *attr, char *buf)
452 {
453 	struct lm87_data *data = lm87_update_device(dev);
454 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_int));
455 }
456 
457 static ssize_t temp2_crit_show(struct device *dev,
458 			       struct device_attribute *attr, char *buf)
459 {
460 	struct lm87_data *data = lm87_update_device(dev);
461 	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_crit_ext));
462 }
463 
464 static DEVICE_ATTR_RO(temp1_crit);
465 static DEVICE_ATTR_RO(temp2_crit);
466 static DEVICE_ATTR(temp3_crit, 0444, temp2_crit_show, NULL);
467 
468 static ssize_t fan_input_show(struct device *dev,
469 			      struct device_attribute *attr, char *buf)
470 {
471 	struct lm87_data *data = lm87_update_device(dev);
472 	int nr = to_sensor_dev_attr(attr)->index;
473 
474 	return sprintf(buf, "%d\n", fan_from_reg(data->fan[nr],
475 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
476 }
477 
478 static ssize_t fan_min_show(struct device *dev, struct device_attribute *attr,
479 			    char *buf)
480 {
481 	struct lm87_data *data = lm87_update_device(dev);
482 	int nr = to_sensor_dev_attr(attr)->index;
483 
484 	return sprintf(buf, "%d\n", fan_from_reg(data->fan_min[nr],
485 		       FAN_DIV_FROM_REG(data->fan_div[nr])));
486 }
487 
488 static ssize_t fan_div_show(struct device *dev, struct device_attribute *attr,
489 			    char *buf)
490 {
491 	struct lm87_data *data = lm87_update_device(dev);
492 	int nr = to_sensor_dev_attr(attr)->index;
493 
494 	return sprintf(buf, "%d\n",
495 		       FAN_DIV_FROM_REG(data->fan_div[nr]));
496 }
497 
498 static ssize_t fan_min_store(struct device *dev,
499 			     struct device_attribute *attr, const char *buf,
500 			     size_t count)
501 {
502 	struct i2c_client *client = dev_get_drvdata(dev);
503 	struct lm87_data *data = i2c_get_clientdata(client);
504 	int nr = to_sensor_dev_attr(attr)->index;
505 	long val;
506 	int err;
507 
508 	err = kstrtol(buf, 10, &val);
509 	if (err)
510 		return err;
511 
512 	mutex_lock(&data->update_lock);
513 	data->fan_min[nr] = FAN_TO_REG(val,
514 			    FAN_DIV_FROM_REG(data->fan_div[nr]));
515 	lm87_write_value(client, LM87_REG_FAN_MIN(nr), data->fan_min[nr]);
516 	mutex_unlock(&data->update_lock);
517 	return count;
518 }
519 
520 /*
521  * Note: we save and restore the fan minimum here, because its value is
522  * determined in part by the fan clock divider.  This follows the principle
523  * of least surprise; the user doesn't expect the fan minimum to change just
524  * because the divider changed.
525  */
526 static ssize_t fan_div_store(struct device *dev,
527 			     struct device_attribute *attr, const char *buf,
528 			     size_t count)
529 {
530 	struct i2c_client *client = dev_get_drvdata(dev);
531 	struct lm87_data *data = i2c_get_clientdata(client);
532 	int nr = to_sensor_dev_attr(attr)->index;
533 	long val;
534 	int err;
535 	unsigned long min;
536 	u8 reg;
537 
538 	err = kstrtol(buf, 10, &val);
539 	if (err)
540 		return err;
541 
542 	mutex_lock(&data->update_lock);
543 	min = fan_from_reg(data->fan_min[nr],
544 			   FAN_DIV_FROM_REG(data->fan_div[nr]));
545 
546 	switch (val) {
547 	case 1:
548 		data->fan_div[nr] = 0;
549 		break;
550 	case 2:
551 		data->fan_div[nr] = 1;
552 		break;
553 	case 4:
554 		data->fan_div[nr] = 2;
555 		break;
556 	case 8:
557 		data->fan_div[nr] = 3;
558 		break;
559 	default:
560 		mutex_unlock(&data->update_lock);
561 		return -EINVAL;
562 	}
563 
564 	reg = lm87_read_value(client, LM87_REG_VID_FAN_DIV);
565 	switch (nr) {
566 	case 0:
567 	    reg = (reg & 0xCF) | (data->fan_div[0] << 4);
568 	    break;
569 	case 1:
570 	    reg = (reg & 0x3F) | (data->fan_div[1] << 6);
571 	    break;
572 	}
573 	lm87_write_value(client, LM87_REG_VID_FAN_DIV, reg);
574 
575 	data->fan_min[nr] = FAN_TO_REG(min, val);
576 	lm87_write_value(client, LM87_REG_FAN_MIN(nr),
577 			 data->fan_min[nr]);
578 	mutex_unlock(&data->update_lock);
579 
580 	return count;
581 }
582 
583 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0);
584 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
585 static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
586 static SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1);
587 static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
588 static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
589 
590 static ssize_t alarms_show(struct device *dev, struct device_attribute *attr,
591 			   char *buf)
592 {
593 	struct lm87_data *data = lm87_update_device(dev);
594 	return sprintf(buf, "%d\n", data->alarms);
595 }
596 static DEVICE_ATTR_RO(alarms);
597 
598 static ssize_t cpu0_vid_show(struct device *dev,
599 			     struct device_attribute *attr, char *buf)
600 {
601 	struct lm87_data *data = lm87_update_device(dev);
602 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
603 }
604 static DEVICE_ATTR_RO(cpu0_vid);
605 
606 static ssize_t vrm_show(struct device *dev, struct device_attribute *attr,
607 			char *buf)
608 {
609 	struct lm87_data *data = dev_get_drvdata(dev);
610 	return sprintf(buf, "%d\n", data->vrm);
611 }
612 static ssize_t vrm_store(struct device *dev, struct device_attribute *attr,
613 			 const char *buf, size_t count)
614 {
615 	struct lm87_data *data = dev_get_drvdata(dev);
616 	unsigned long val;
617 	int err;
618 
619 	err = kstrtoul(buf, 10, &val);
620 	if (err)
621 		return err;
622 
623 	if (val > 255)
624 		return -EINVAL;
625 
626 	data->vrm = val;
627 	return count;
628 }
629 static DEVICE_ATTR_RW(vrm);
630 
631 static ssize_t aout_output_show(struct device *dev,
632 				struct device_attribute *attr, char *buf)
633 {
634 	struct lm87_data *data = lm87_update_device(dev);
635 	return sprintf(buf, "%d\n", AOUT_FROM_REG(data->aout));
636 }
637 static ssize_t aout_output_store(struct device *dev,
638 				 struct device_attribute *attr,
639 				 const char *buf, size_t count)
640 {
641 	struct i2c_client *client = dev_get_drvdata(dev);
642 	struct lm87_data *data = i2c_get_clientdata(client);
643 	long val;
644 	int err;
645 
646 	err = kstrtol(buf, 10, &val);
647 	if (err)
648 		return err;
649 
650 	mutex_lock(&data->update_lock);
651 	data->aout = AOUT_TO_REG(val);
652 	lm87_write_value(client, LM87_REG_AOUT, data->aout);
653 	mutex_unlock(&data->update_lock);
654 	return count;
655 }
656 static DEVICE_ATTR_RW(aout_output);
657 
658 static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
659 			  char *buf)
660 {
661 	struct lm87_data *data = lm87_update_device(dev);
662 	int bitnr = to_sensor_dev_attr(attr)->index;
663 	return sprintf(buf, "%u\n", (data->alarms >> bitnr) & 1);
664 }
665 static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
666 static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
667 static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
668 static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
669 static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
670 static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 9);
671 static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 6);
672 static SENSOR_DEVICE_ATTR_RO(in7_alarm, alarm, 7);
673 static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
674 static SENSOR_DEVICE_ATTR_RO(temp2_alarm, alarm, 5);
675 static SENSOR_DEVICE_ATTR_RO(temp3_alarm, alarm, 5);
676 static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
677 static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
678 static SENSOR_DEVICE_ATTR_RO(temp2_fault, alarm, 14);
679 static SENSOR_DEVICE_ATTR_RO(temp3_fault, alarm, 15);
680 
681 /*
682  * Real code
683  */
684 
685 static struct attribute *lm87_attributes[] = {
686 	&sensor_dev_attr_in1_input.dev_attr.attr,
687 	&sensor_dev_attr_in1_min.dev_attr.attr,
688 	&sensor_dev_attr_in1_max.dev_attr.attr,
689 	&sensor_dev_attr_in1_alarm.dev_attr.attr,
690 	&sensor_dev_attr_in2_input.dev_attr.attr,
691 	&sensor_dev_attr_in2_min.dev_attr.attr,
692 	&sensor_dev_attr_in2_max.dev_attr.attr,
693 	&sensor_dev_attr_in2_alarm.dev_attr.attr,
694 	&sensor_dev_attr_in3_input.dev_attr.attr,
695 	&sensor_dev_attr_in3_min.dev_attr.attr,
696 	&sensor_dev_attr_in3_max.dev_attr.attr,
697 	&sensor_dev_attr_in3_alarm.dev_attr.attr,
698 	&sensor_dev_attr_in4_input.dev_attr.attr,
699 	&sensor_dev_attr_in4_min.dev_attr.attr,
700 	&sensor_dev_attr_in4_max.dev_attr.attr,
701 	&sensor_dev_attr_in4_alarm.dev_attr.attr,
702 
703 	&sensor_dev_attr_temp1_input.dev_attr.attr,
704 	&sensor_dev_attr_temp1_max.dev_attr.attr,
705 	&sensor_dev_attr_temp1_min.dev_attr.attr,
706 	&dev_attr_temp1_crit.attr,
707 	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
708 	&sensor_dev_attr_temp2_input.dev_attr.attr,
709 	&sensor_dev_attr_temp2_max.dev_attr.attr,
710 	&sensor_dev_attr_temp2_min.dev_attr.attr,
711 	&dev_attr_temp2_crit.attr,
712 	&sensor_dev_attr_temp2_alarm.dev_attr.attr,
713 	&sensor_dev_attr_temp2_fault.dev_attr.attr,
714 
715 	&dev_attr_alarms.attr,
716 	&dev_attr_aout_output.attr,
717 
718 	NULL
719 };
720 
721 static const struct attribute_group lm87_group = {
722 	.attrs = lm87_attributes,
723 };
724 
725 static struct attribute *lm87_attributes_in6[] = {
726 	&sensor_dev_attr_in6_input.dev_attr.attr,
727 	&sensor_dev_attr_in6_min.dev_attr.attr,
728 	&sensor_dev_attr_in6_max.dev_attr.attr,
729 	&sensor_dev_attr_in6_alarm.dev_attr.attr,
730 	NULL
731 };
732 
733 static const struct attribute_group lm87_group_in6 = {
734 	.attrs = lm87_attributes_in6,
735 };
736 
737 static struct attribute *lm87_attributes_fan1[] = {
738 	&sensor_dev_attr_fan1_input.dev_attr.attr,
739 	&sensor_dev_attr_fan1_min.dev_attr.attr,
740 	&sensor_dev_attr_fan1_div.dev_attr.attr,
741 	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
742 	NULL
743 };
744 
745 static const struct attribute_group lm87_group_fan1 = {
746 	.attrs = lm87_attributes_fan1,
747 };
748 
749 static struct attribute *lm87_attributes_in7[] = {
750 	&sensor_dev_attr_in7_input.dev_attr.attr,
751 	&sensor_dev_attr_in7_min.dev_attr.attr,
752 	&sensor_dev_attr_in7_max.dev_attr.attr,
753 	&sensor_dev_attr_in7_alarm.dev_attr.attr,
754 	NULL
755 };
756 
757 static const struct attribute_group lm87_group_in7 = {
758 	.attrs = lm87_attributes_in7,
759 };
760 
761 static struct attribute *lm87_attributes_fan2[] = {
762 	&sensor_dev_attr_fan2_input.dev_attr.attr,
763 	&sensor_dev_attr_fan2_min.dev_attr.attr,
764 	&sensor_dev_attr_fan2_div.dev_attr.attr,
765 	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
766 	NULL
767 };
768 
769 static const struct attribute_group lm87_group_fan2 = {
770 	.attrs = lm87_attributes_fan2,
771 };
772 
773 static struct attribute *lm87_attributes_temp3[] = {
774 	&sensor_dev_attr_temp3_input.dev_attr.attr,
775 	&sensor_dev_attr_temp3_max.dev_attr.attr,
776 	&sensor_dev_attr_temp3_min.dev_attr.attr,
777 	&dev_attr_temp3_crit.attr,
778 	&sensor_dev_attr_temp3_alarm.dev_attr.attr,
779 	&sensor_dev_attr_temp3_fault.dev_attr.attr,
780 	NULL
781 };
782 
783 static const struct attribute_group lm87_group_temp3 = {
784 	.attrs = lm87_attributes_temp3,
785 };
786 
787 static struct attribute *lm87_attributes_in0_5[] = {
788 	&sensor_dev_attr_in0_input.dev_attr.attr,
789 	&sensor_dev_attr_in0_min.dev_attr.attr,
790 	&sensor_dev_attr_in0_max.dev_attr.attr,
791 	&sensor_dev_attr_in0_alarm.dev_attr.attr,
792 	&sensor_dev_attr_in5_input.dev_attr.attr,
793 	&sensor_dev_attr_in5_min.dev_attr.attr,
794 	&sensor_dev_attr_in5_max.dev_attr.attr,
795 	&sensor_dev_attr_in5_alarm.dev_attr.attr,
796 	NULL
797 };
798 
799 static const struct attribute_group lm87_group_in0_5 = {
800 	.attrs = lm87_attributes_in0_5,
801 };
802 
803 static struct attribute *lm87_attributes_vid[] = {
804 	&dev_attr_cpu0_vid.attr,
805 	&dev_attr_vrm.attr,
806 	NULL
807 };
808 
809 static const struct attribute_group lm87_group_vid = {
810 	.attrs = lm87_attributes_vid,
811 };
812 
813 /* Return 0 if detection is successful, -ENODEV otherwise */
814 static int lm87_detect(struct i2c_client *client, struct i2c_board_info *info)
815 {
816 	struct i2c_adapter *adapter = client->adapter;
817 	const char *name;
818 	u8 cid, rev;
819 
820 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
821 		return -ENODEV;
822 
823 	if (lm87_read_value(client, LM87_REG_CONFIG) & 0x80)
824 		return -ENODEV;
825 
826 	/* Now, we do the remaining detection. */
827 	cid = lm87_read_value(client, LM87_REG_COMPANY_ID);
828 	rev = lm87_read_value(client, LM87_REG_REVISION);
829 
830 	if (cid == 0x02			/* National Semiconductor */
831 	 && (rev >= 0x01 && rev <= 0x08))
832 		name = "lm87";
833 	else if (cid == 0x41		/* Analog Devices */
834 	      && (rev & 0xf0) == 0x10)
835 		name = "adm1024";
836 	else {
837 		dev_dbg(&adapter->dev, "LM87 detection failed at 0x%02x\n",
838 			client->addr);
839 		return -ENODEV;
840 	}
841 
842 	strscpy(info->type, name, I2C_NAME_SIZE);
843 
844 	return 0;
845 }
846 
847 static void lm87_restore_config(void *arg)
848 {
849 	struct i2c_client *client = arg;
850 	struct lm87_data *data = i2c_get_clientdata(client);
851 
852 	lm87_write_value(client, LM87_REG_CONFIG, data->config);
853 }
854 
855 static int lm87_init_client(struct i2c_client *client)
856 {
857 	struct lm87_data *data = i2c_get_clientdata(client);
858 	int rc;
859 	struct device_node *of_node = client->dev.of_node;
860 	u8 val = 0;
861 	struct regulator *vcc = NULL;
862 
863 	if (of_node) {
864 		if (of_property_read_bool(of_node, "has-temp3"))
865 			val |= CHAN_TEMP3;
866 		if (of_property_read_bool(of_node, "has-in6"))
867 			val |= CHAN_NO_FAN(0);
868 		if (of_property_read_bool(of_node, "has-in7"))
869 			val |= CHAN_NO_FAN(1);
870 		vcc = devm_regulator_get_optional(&client->dev, "vcc");
871 		if (!IS_ERR(vcc)) {
872 			if (regulator_get_voltage(vcc) == 5000000)
873 				val |= CHAN_VCC_5V;
874 		}
875 		data->channel = val;
876 		lm87_write_value(client,
877 				LM87_REG_CHANNEL_MODE, data->channel);
878 	} else if (dev_get_platdata(&client->dev)) {
879 		data->channel = *(u8 *)dev_get_platdata(&client->dev);
880 		lm87_write_value(client,
881 				 LM87_REG_CHANNEL_MODE, data->channel);
882 	} else {
883 		data->channel = lm87_read_value(client, LM87_REG_CHANNEL_MODE);
884 	}
885 	data->config = lm87_read_value(client, LM87_REG_CONFIG) & 0x6F;
886 
887 	rc = devm_add_action(&client->dev, lm87_restore_config, client);
888 	if (rc)
889 		return rc;
890 
891 	if (!(data->config & 0x01)) {
892 		int i;
893 
894 		/* Limits are left uninitialized after power-up */
895 		for (i = 1; i < 6; i++) {
896 			lm87_write_value(client, LM87_REG_IN_MIN(i), 0x00);
897 			lm87_write_value(client, LM87_REG_IN_MAX(i), 0xFF);
898 		}
899 		for (i = 0; i < 2; i++) {
900 			lm87_write_value(client, LM87_REG_TEMP_HIGH[i], 0x7F);
901 			lm87_write_value(client, LM87_REG_TEMP_LOW[i], 0x00);
902 			lm87_write_value(client, LM87_REG_AIN_MIN(i), 0x00);
903 			lm87_write_value(client, LM87_REG_AIN_MAX(i), 0xFF);
904 		}
905 		if (data->channel & CHAN_TEMP3) {
906 			lm87_write_value(client, LM87_REG_TEMP_HIGH[2], 0x7F);
907 			lm87_write_value(client, LM87_REG_TEMP_LOW[2], 0x00);
908 		} else {
909 			lm87_write_value(client, LM87_REG_IN_MIN(0), 0x00);
910 			lm87_write_value(client, LM87_REG_IN_MAX(0), 0xFF);
911 		}
912 	}
913 
914 	/* Make sure Start is set and INT#_Clear is clear */
915 	if ((data->config & 0x09) != 0x01)
916 		lm87_write_value(client, LM87_REG_CONFIG,
917 				 (data->config & 0x77) | 0x01);
918 	return 0;
919 }
920 
921 static int lm87_probe(struct i2c_client *client)
922 {
923 	struct lm87_data *data;
924 	struct device *hwmon_dev;
925 	int err;
926 	unsigned int group_tail = 0;
927 
928 	data = devm_kzalloc(&client->dev, sizeof(struct lm87_data), GFP_KERNEL);
929 	if (!data)
930 		return -ENOMEM;
931 
932 	i2c_set_clientdata(client, data);
933 	mutex_init(&data->update_lock);
934 
935 	/* Initialize the LM87 chip */
936 	err = lm87_init_client(client);
937 	if (err)
938 		return err;
939 
940 	data->in_scale[0] = 2500;
941 	data->in_scale[1] = 2700;
942 	data->in_scale[2] = (data->channel & CHAN_VCC_5V) ? 5000 : 3300;
943 	data->in_scale[3] = 5000;
944 	data->in_scale[4] = 12000;
945 	data->in_scale[5] = 2700;
946 	data->in_scale[6] = 1875;
947 	data->in_scale[7] = 1875;
948 
949 	/*
950 	 * Construct the list of attributes, the list depends on the
951 	 * configuration of the chip
952 	 */
953 	data->attr_groups[group_tail++] = &lm87_group;
954 	if (data->channel & CHAN_NO_FAN(0))
955 		data->attr_groups[group_tail++] = &lm87_group_in6;
956 	else
957 		data->attr_groups[group_tail++] = &lm87_group_fan1;
958 
959 	if (data->channel & CHAN_NO_FAN(1))
960 		data->attr_groups[group_tail++] = &lm87_group_in7;
961 	else
962 		data->attr_groups[group_tail++] = &lm87_group_fan2;
963 
964 	if (data->channel & CHAN_TEMP3)
965 		data->attr_groups[group_tail++] = &lm87_group_temp3;
966 	else
967 		data->attr_groups[group_tail++] = &lm87_group_in0_5;
968 
969 	if (!(data->channel & CHAN_NO_VID)) {
970 		data->vrm = vid_which_vrm();
971 		data->attr_groups[group_tail++] = &lm87_group_vid;
972 	}
973 
974 	hwmon_dev = devm_hwmon_device_register_with_groups(
975 	    &client->dev, client->name, client, data->attr_groups);
976 	return PTR_ERR_OR_ZERO(hwmon_dev);
977 }
978 
979 /*
980  * Driver data (common to all clients)
981  */
982 
983 static const struct i2c_device_id lm87_id[] = {
984 	{ "lm87" },
985 	{ "adm1024" },
986 	{ }
987 };
988 MODULE_DEVICE_TABLE(i2c, lm87_id);
989 
990 static const struct of_device_id lm87_of_match[] = {
991 	{ .compatible = "ti,lm87" },
992 	{ .compatible = "adi,adm1024" },
993 	{ },
994 };
995 MODULE_DEVICE_TABLE(of, lm87_of_match);
996 
997 static struct i2c_driver lm87_driver = {
998 	.class		= I2C_CLASS_HWMON,
999 	.driver = {
1000 		.name	= "lm87",
1001 		.of_match_table = lm87_of_match,
1002 	},
1003 	.probe		= lm87_probe,
1004 	.id_table	= lm87_id,
1005 	.detect		= lm87_detect,
1006 	.address_list	= normal_i2c,
1007 };
1008 
1009 module_i2c_driver(lm87_driver);
1010 
1011 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de> and others");
1012 MODULE_DESCRIPTION("LM87 driver");
1013 MODULE_LICENSE("GPL");
1014